U.S. Pat. No. 4,770,641 granted Sept. 13, 1988 deals with a conductive gel interconnection apparatus which is used to establish electrical interconnection between a plurality of associated conductors such as wires, conductive traces on printed circuit boards, pin grid arrays or other components where there are closely spaced conductors positioned in an array on a substrate. The apparatus uses an insulative body having one or more open-ended cavities containing a conductive gel which is brought into contact with two discrete electrical elements to provide an interconnection therebetween. The patent deals with a disconnectable type of connector and with a particular type of gel which, while conforming to the housing cavities in which it is used, is sufficiently coherent and viscous that it will not flow from the cavity, and upon disconnection of the elements will return to its original shape and remain within the housing cavities.
The advantage of the foregoing mentioned patent in one major respect is that the so-called contact forces of engagement, or forces of withdrawal from the gel, are minimal as compared with traditional connectors. Specifically, traditional electrical connectors require normal forces of interconnection in the range between 50 grams for gold plated contacts to over 200 grams for tin plated contacts, as bare minimums for connectors which experience modest environments. Conductive gel contacts involve normal forces of a few grams for the gel connect and disconnect functions.
The present invention has as an object an improvement over the foregoing mentioned patent with respect to the provision of conductive gel interconnections. A further object is to provide an area array connector which can be connected and disconnected with minimum forces of engagement to allow high numbers of contact points such as experienced in pin grid arrays to be interconnected and disconnected repeatedly. A still further object is to provide an inexpensive, area array, interposer type interconnection system for packaging electrical and electronic components such as integrated circuits. A still further object is to provide a high compliance, low-force and environmentally sealed connector in an inexpensive package.